Jon Lester threw a problem-free bullpen session this morning and is scheduled to return from the disabled list Monday against the Royals.

Lester hasn’t pitched since July 5 because of a strained left latissimus, but manager Terry Francona told Tim Britton of the Providence Journal that the left-hander is healthy now and simply needs to build back his arm strength:

There’s no issues. That’s good. We’re just trying to ramp him up and let him get strong. He feels nothing in that lat, which is great. That’s what we wanted. Now it’s just the idea of getting him back to where he can go out there and start a game and not be so limited to where he can only throw 50 pitches.

According to Britton the pitch count for Monday’s start figures to be around 80 or 90. Aside from leaving the July 5 outing early, Lester hasn’t thrown fewer than 93 pitches in a start since Opening Day.